In the case where a plurality of users share a file with the use of terminals such as a personal computer and a smartphone, there is a method in which an address of a storage location of the file is exchanged via emails, instant messengers, or the like, thereby sharing the file.
As another method, an address of a storage location of a file is exchanged between terminals via communication such as infrared communication or Bluetooth (registered trademark), thereby sharing the file. PTL 1 proposes to transmit/receive file data via optical communication.